Refuting the sceptical arguments
In Meditation 1, Descartes appeared to demolish all knowledge claims. As we have seen he then went on to establish the cogito as the first principle of philosophy and from that self-authenticating statement he was able to build knowledge upon this foundational truth. In Meditation 6 Descartes was now keen to revisit the sceptical arguments that he used in Meditation 1 and show that with a careful use of reason even these most extreme arguments can be refuted. In Mediation 6 Descartes showed that he could know with certainty that there is an outside world; that with careful use of reason we can trust our senses; that we can ‘know’ that we aren’t in fact dreaming.
You may remember the term ‘solipsism’ from the earlier part of the course. This was raised as a criticism of empiricism. Strictly speaking, if knowledge claims can only be rooted in sense experience then all we can actually know for sure are the experiences of our own minds. When Descartes attempted to refute the sceptical arguments in Meditation 6 he was attempting to show clearly that reason alone could lead us beyond solipsism. If he was successful then he would have overcome the tradition of radical scepticism and show that rationalism is superior to empiricism.
Descartes’ lengthy discussions about proving that there is an outside world were an attempt to show that he can overcome this well-known philosophical tradition.
There are three sceptical arguments that Descartes attempted to refute.
God is no deceiver therefore material reality exists
Descartes’ strategy to show that he could know with certainty that the material world is a reality relies on the clear and distinct rule and his proof that God exists and is good.
Commonsense tells us that the source of our sensations of the world around us must surely originate in the physical objects themselves. But could Descartes successfully prove this simple piece of common sense knowledge?
An argument for the existence of material things
‘It remains for me to examine whether material things exist.’
Descartes’ argument can be split into two simple steps. The argument is based around the simple sensation that we all have of the world around us. At this moment you are reading a philosophy document. You are seeing paper, text, your hands and possibly a desk in the background. Descartes asks a very simple question; where do these sensations come from? His mind tells him that there are only three possible answers to this question. The sensations of the world outside his mind can only possibly originate from either his own mind, from the actual outside world or from God choosing to put these sensations into our mind.
Step 1: The sensations we have of materials things come from outside the mind.
First Descartes wishes to make clear that the sensations he has in his mind of materials things do not originate from within his own mind. To justify his conclusion he presents two simple arguments.
First of all he points out simply that these sensations are not subject to his will. He cannot control their appearance or their smell. His mind then cannot have willed these sensations. They must, therefore, have come from outside his mind.
Second, he points out that his sensations of material things give him the idea that they are extended things. In other words they appear to represent things which have size and shape. His mind, however, is unextended, it has no size or shape. Descartes argues that an unextended thing (the mind) cannot create or cause the idea of an extended thing. Therefore the sensations that we have of material things must come from outside his mind.
Step 2: The sensations we have of materials things must originate in physical matter itself.
If the sensations that we have of material things don’t originate in our minds, where do they come from? There are, according to Descartes, only two possibilities. Either they come from the material world itself or they come from God. Descartes simply points out that he has a strong inclination to believe that there is a physical world. He has already shown that God must exist and that this God must be good (perfection cannot include any idea of deception). Therefore, God would not give us ideas about an outside world (a world beyond our mind) if it wasn’t in fact true. God is no deceiver; therefore the sensations of the physical world could not come from God. The only possibility left is that they must originate in the material objects themselves.
Activity
Try to present Descartes’ argument for the existence of an outside world in standard form. There will be an intermediate and a final conclusion.
Before you do so, read carefully the extract from Meditation 6 below.
Try to find useful quotes also that you could use to help explain Descartes’ argument.
Descartes’ argument can be summarised as follows:
Our intellect should take priority over our imagination.
The intellect can understand the primary qualities of objects clearly and distinctly.
God is no deceiver and so we can have knowledge of the primary qualities of objects.
If we can have knowledge of the primary qualities of objects, we can therefore have knowledge of the essence of the objects.
God is no deceiver and so we can trust our senses to give us a good representation of the secondary qualities of the objects.
Conclusion: With a careful use of our God-given reason, errors in sense perception can be recognised and corrected.
In Meditation 1, Descartes appeared to demolish all knowledge claims. As we have seen he then went on to establish the cogito as the first principle of philosophy and from that self-authenticating statement he was able to build knowledge upon this foundational truth. In Meditation 6 Descartes was now keen to revisit the sceptical arguments that he used in Meditation 1 and show that with a careful use of reason even these most extreme arguments can be refuted. In Mediation 6 Descartes showed that he could know with certainty that there is an outside world; that with careful use of reason we can trust our senses; that we can ‘know’ that we aren’t in fact dreaming.
You may remember the term ‘solipsism’ from the earlier part of the course. This was raised as a criticism of empiricism. Strictly speaking, if knowledge claims can only be rooted in sense experience then all we can actually know for sure are the experiences of our own minds. When Descartes attempted to refute the sceptical arguments in Meditation 6 he was attempting to show clearly that reason alone could lead us beyond solipsism. If he was successful then he would have overcome the tradition of radical scepticism and show that rationalism is superior to empiricism.
Descartes’ lengthy discussions about proving that there is an outside world were an attempt to show that he can overcome this well-known philosophical tradition.
There are three sceptical arguments that Descartes attempted to refute.
God is no deceiver therefore material reality exists
Descartes’ strategy to show that he could know with certainty that the material world is a reality relies on the clear and distinct rule and his proof that God exists and is good.
Commonsense tells us that the source of our sensations of the world around us must surely originate in the physical objects themselves. But could Descartes successfully prove this simple piece of common sense knowledge?
An argument for the existence of material things
‘It remains for me to examine whether material things exist.’
Descartes’ argument can be split into two simple steps. The argument is based around the simple sensation that we all have of the world around us. At this moment you are reading a philosophy document. You are seeing paper, text, your hands and possibly a desk in the background. Descartes asks a very simple question; where do these sensations come from? His mind tells him that there are only three possible answers to this question. The sensations of the world outside his mind can only possibly originate from either his own mind, from the actual outside world or from God choosing to put these sensations into our mind.
Step 1: The sensations we have of materials things come from outside the mind.
First Descartes wishes to make clear that the sensations he has in his mind of materials things do not originate from within his own mind. To justify his conclusion he presents two simple arguments.
First of all he points out simply that these sensations are not subject to his will. He cannot control their appearance or their smell. His mind then cannot have willed these sensations. They must, therefore, have come from outside his mind.
Second, he points out that his sensations of material things give him the idea that they are extended things. In other words they appear to represent things which have size and shape. His mind, however, is unextended, it has no size or shape. Descartes argues that an unextended thing (the mind) cannot create or cause the idea of an extended thing. Therefore the sensations that we have of material things must come from outside his mind.
Step 2: The sensations we have of materials things must originate in physical matter itself.
If the sensations that we have of material things don’t originate in our minds, where do they come from? There are, according to Descartes, only two possibilities. Either they come from the material world itself or they come from God. Descartes simply points out that he has a strong inclination to believe that there is a physical world. He has already shown that God must exist and that this God must be good (perfection cannot include any idea of deception). Therefore, God would not give us ideas about an outside world (a world beyond our mind) if it wasn’t in fact true. God is no deceiver; therefore the sensations of the physical world could not come from God. The only possibility left is that they must originate in the material objects themselves.
Activity
Try to present Descartes’ argument for the existence of an outside world in standard form. There will be an intermediate and a final conclusion.
Before you do so, read carefully the extract from Meditation 6 below.
Try to find useful quotes also that you could use to help explain Descartes’ argument.
Descartes’ argument can be summarised as follows:
Conclusion: With a careful use of our God-given reason, errors in sense perception can be recognised and corrected.